Predictive factors for acute symptomatic esophagitis in 256 patients with locally advanced non-small cell lung cancer treated with intensity-modulated radiation therapy

Abstract

Objective To explore the incidence and related predictive factors for acute symptomatic esophagitis in patients with locally advanced non-small cell lung cancer (NSCLC) treated with intensity-modulated radiation therapy (IMRT). Methods Data were collected retrospectively from 256 patients with inoperable or unresectable stage Ⅲ NSCLC treated in our hospital between January 2007 and December 2011.The radiotherapy target volume included primary lung cancer and lymphatic drainage area involved, with a median dose of 60 Gy in 30 fractions (50-70 Gy). Of all the patients, 109 patients (42.6%) received concurrent chemotherapy. Grade ≥2 acute esophagitis (AE)(symptomatic esophagitis) which occurred during radiotherapy and within 3 months after completion of radiotherapy served as the outcome event. National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0(NCI-CTCAE3.0) was used to evaluate the grade of AE.The logistic regression model was used to analyze the predictive factors. Results A total of 174 patients (68%) had treatment-related grade ≥2 AE; 154 patients (60.2%) had grade 2 AE and 20 patients (7.8%) had grade 3 AE.The median dose when grade ≥2 AE occurred was 30 Gy (11-68 Gy). For grade ≥2 AE, multivariate analysis showed that esophageal V5-V60, mean dose, and age were independent predictive factors (P=0.021, 0, 0.010). For grade ≥3 AE, multivariate analysis showed that esophageal V50-V60, concurrent chemotherapy, and body mass index (BMI) were independent predictive factors (P=0.010, 0.003, 0.019). Old age and higher BMI were the protective factors for grade ≥2 and≥3 AE, respectively. Conclusions For patients with locally advanced NSCLC treated with IMRT, esophageal V50–V60 and concurrent chemotherapy are predictive factors for grade ≥3 AE, and esophageal V50 has a high predictive value for both grade ≥2 and ≥3 AE. Key words: Cacinoma, non-small cell lung/intensity modulated radiotherapy; Cacinoma, non-small cell lung/chemotherapy; Acute symptomatic esophagitis